--  @testpoint:opengauss关键字breadth(非保留)，作为函数名
--关键字不带引号-成功
drop function if exists breadth;
create function breadth(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--清理环境
drop function breadth;

--关键字带双引号-成功
drop function if exists "breadth";
create function "breadth"(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--清理环境
drop function "breadth";

--关键字带单引号-合理报错
drop function if exists 'breadth';
create function 'breadth'(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/

--关键字带反引号-合理报错
drop function if exists `breadth`;
create function `breadth`(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/